a widely-expressed Rab GTPase-activating protein which apparently plays a role in mediating insulin action. Phosphorylated by the Ser/Thr protein kinase Akt in response to insulin. Is redistributed from low-density microsomes to the cytosol upon insulin treatment. Insulin stimulation of GLUT4 exocytosis is dependent on AS160. The translocation of GLUT4 from intracellular storage sites to the cell surface functions to stimulate insulin uptake by adipose and muscle tissue. Its expression is decreased by twofold in pancreatic islets in type 2 diabetes patients compared to control subjects; its phosphorylation is impaired in skeletal muscle of type 2 diabetics. The protein is expressed in pancreatic Langerhans islets, including beta cells. Up-regulated in T cells from patients with atopic dermatitis. Two alternatively spliced isoforms have been described. Isoform 2, which promotes GLUT4 translocation at the plasma membrane, is the highest overexpressed in most tissues. Isoform 2 shows a cytoplasmic perinuclear localization in a myoblastic cell line in resting and insulin-stimulated cells Isoform 2 is strongly expressed in adrenal and thyroid gland, and also in lung, kidney, colon, brain and adipose tissue. Isoform 2 is moderately expressed in skeletal muscle. Isoform 1 is highly expressed in skeletal muscle and heart, but was not detectable in the liver or adipose tissue. Note: This description may include information from UniProtKB.
Protein type: GAPs; GAPs, Rab
Cellular Component: cytoplasmic vesicle membrane
Molecular Function: Rab GTPase activator activity
Biological Process: vesicle-mediated transport; negative regulation of vesicle fusion; cellular response to insulin stimulus
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.